Replaceable flexible abrasive unit for polishing sheets and panels



Sept. 3, 1957 A. BLOCK,

REPLACEABLE FLEXIBLE ABRASIVE UNIT FOR POLISHING SHEETS AND PANELS FiledJune 20, 1955 llllllk Here-- K m L K C E. L A

IN VEN TOR.

HlS ATTORNEY 1% rummuw- HIMW REPLACEABLE FLEXIBLE ABRASIVE UNIT FORPOLISHENG SHEETS AND PANELS Aleck block, Culver City, Calif., assignorto Merit Products, Ina, Culver City, Calif, a corporation of CaliforniaApplication June 20, 1955, Serial No. 516,536

2 Claims. (Cl. 51-1935) This invention relates to a flexible abrasiveunit which is replaceable and which is adapted for use in polishingsheets and panels.

My flexible abrasive unit is particularly designed for use in connectionwith a large drum for polishing sheets and panels of considerable size.My unit is, however, capable of use in the same or in suitably modifiedform in other devices and constructions for the same or other abrasivepurposes.

It is an object of my invention to provide a replacement unit which maybe simply and quickly installed upon and removed from a drum orrotatable member of considerable length and which can preferably beinserted and removed from one end of the drum. Since my abrasive unitextends along substantially the entire length of the drum, it mustnecessarily possess a certain amount of rigidity in order to permit suchinsertion.

It is a further object of my invention to provide an abrasive unit whichis capable of use in association with an adjacent brush, with the brushgently wiping the abrasive material into contact with the surface areaof the sheet or panel being polished. My abrasive unit must accordinglypossess a considerable amount of flexibility, preferably greater thanthat of a conventional sheet of abrasive coated paper.

Another object of my invention is to provide a replaceable abrasive unitwhich is simple in construction and economical in cost. My abrasive unitis formed of the most economical materials which are assembled in assimple and economical a manner as possible.

Another object of my invention is to provide an abrasive unit of theclass described which can be mounted on and removed from a rotatablemember from the outside thereof without requiring disassembly of therotatable member and without requiring moving parts or adjustments ofany kind.

In essence, my invention contemplates a replaceable flexible abrasiveunit for polishing large areas, said abrasive unit having asubstantially rigid base member. An elongated band of substantiallyflexible material such as textile or the like which is substantiallyequal in length to the base member is attached thereto along one edge.An elongated band of abrasive material substantially equal in length tothe base member is attached to the opposite edge of the flexible band.The opposite edge of the abrasive band is free and contacts the materialbeing polished. This provides a unit which possesses the desiredcombination of rigidity, flexibility and economy, as will be moreclearly set forth later in this application.

My invention also comprises such other objects, advantages andcapabilities as Will later more fully appear and which are inherentlypossessed by my invention.

While I have shown in the accompanying drawings a preferred embodimentof my invention, it should be understood that the same is susceptible ofmodification and change without departing from the spirit of myinvention.

Referring to the drawings, Fig. l is a plan view of one side of my unit;

Fig. 2 is a plan view of the opposite side;

Fig. 3 is a sectional view taken on line 3-3 of Fig. 2;

Fig. 4 is an end perspective view of a track showing my unit in usetherein;

Fig. 5 is an end view of an abrasive drum showing my unit in usetherein;

Fig. 6 is a side view of an abrasive drum showing my unit in usetherein.

A preferred embodiment which has been selected to illustrate myinvention comprises an elongated base member 10, which is preferablyformed of substantially rigid material. The word rigid is used in thesense that the material is substantially self-supporting so that it canbe inserted into an elongated track Without buck material is not rigidand is preferably more flexible than the base member 10 and moreflexible than conventional abrasive coated paper. Flexible band 11 ispreferably formed of textile material, although other suitable materialssuch as equivalent plastics and other substances may also be used.

One edge of flexible band 11 is bent to form a loop 12, which extendsaround base member lil. A plurality of staples 23 extend through bothsides of loop 12 and through base member 10 along the entire lengththereof to attach one edge of flexible band 11 securely to base member10.

An elongated abrasive band 13 is substantially equal in length to basemember 10 and flexible band 11. Abrasive band 13 is preferably formed ofpaper or other suitable material which is coated on one side thereofwith a plurality of small abrasive particles of the type suitable forthe particular abrasive or polishing use. One edge of abrasive band 13is attached to the other edge of flexible band 11 along the entirelength thereof. The means of attachment used preferably comprisesapplying vinyl glue or other suitable liquid adhesive between one sideof the edge of flexible band 11 and the back edge of abrasive band 13.It is also possible to use adhesive to attach flexible band llto basemember 10 and both assembly operations might be performed at the sametime to reduce manufacturing costs.

The opposite edge of abrasive band 13 is left free and is adapted toengage the surface of the sheet or panel to perform the polishingoperation. The free edge of abrasive band 13 may be left intact or maybe provided with a plurality of transverse scores 14, which arepreferably evenly spaced along the entire free edge of abrasive band 13.The advantage of scores 14 is that they provide a plurality of adjacentportions of abrasive material which are free to move relativelyindependently from each other. In case the material being polished hashigh or low spots or other irregularities, one or more portions ofabrasive material can move into or around such high or low spots Withoutaffecting the action of the adjacent portions of abrasive or adverselyaffecting the polishing of adjacent areas of the material beingpolished.

My replaceable abrasive unit is particularly adapted for use in anabrasive assembly for polishing flat sheets, plates and panels. Suchassembly may comprise a hollow cylindrical drum 15, which is rotatablymounted with respect to the material being polished. The drum hasmounted along the entire outside thereof a plurality of tracks 16 whichextend along substantially the entire length of drum 15 and are evenlyspaced therearound. Each track 16 actually comprises a pair of adjacentchannels, one being a brush channels 17 and the other an abrasivechannel 18. The brush channel 17 is substantially square in shape, withan opening along the center of the top edge thereof. A brush 19 ismounted in brush channel 17 by sliding it into the end of the channel.The base of brush 19 is held therein because it is larger than theopening in the top of brush channel 17.

My replaceable abrasive unit is adapted to be inserted into the end ofabrasive channel 18 and slid along the channel until it extendssubstantially from one end of drum 15 to the other. Base member providessuflicient rigidity for my unit so that the unit may be made insubstantially any length for substantially any size of drum. Base member10 acts to prevent any buckling or binding of the unit during insertionand permits easy and quick replacement of the abrasive unit with accessto only one end of drum 15.

Base member 10 corresponds to the shape of abrasive channel 18 and issecurely held therein, with flexible band 11 curving around the top edgeof abrasive channel 18 and extending adjacent the lower portion of brush19. The abrasive band 13 is disposed adjacent the ends of the bristlesof brush 19.

It will be noted that in my abrasive unit the abrasive material isprovided only adjacent the free bristle ends of the brush 19. Thisabrasive material is brushed or wiped against the surface being polishedand becomes worn, requiring replacement. In the past, this replacementhas often been accomplished from the interior of a rotatable member byfeeding out a length of abrasive. With my unit, however, the replacementis accomplished more easily and qiuckly from the exterior of therotatable member.

In use, the portion of the abrasive unit between the edge of abrasiveband 13 and track 16 does not contact the material being polished andwill not become worn. The use of -a flexible band 11 thus avoids wastingexpensive abrasive material, the cost of a textile band beingapproximately half the cost of a comparable piece of abrasive material.

My construction further assures replacement by the user at the propertime. If a large area of intact abrasive were left in the lower half ofthe replaceable abrasive unit, the user might through error or throughfale economy think that the unit need not be replaced, even though theabrasive material had been completely worn from the end of the unit.With my construction, the need for replacement can easily be observed bythe user and there is no hesitancy about wasting unused abrasivematerial.

It should also be noted that the flexible band 11 is preferably moreflexible than the sheet of paper which forms abrasive band 13. Thismeans that the entire abrasive unit is more flexible and can respondmore readily to surface variations in the material being polished. Thepresence of flexible band 11 provides flexibility along the entirelength of the abrasive unit, so that different parts thereof can movewith respect to one another to fit the contours of the material beingpolished. In use, this permits my abrasive unit to be used in polishingmaterial having a radius or having variations from a completely flatsurface. Such material could not properly be reached and polished by aninflexible abrasive unit.

My replaceable abrasive unit thus provides a unique and desirablecombination of rigidity for easy loading and replacement, flexibilityfor increased range of polishing action, and economy resulting from theuse of a minimum amout of abrasive material.

I claim:

1. A replaceable flexible abrasive unit for polishing large areascomprising an elongated narrow base member formed of cardboard or thelike, an elongated flat flexible band of textile material substantiallyequal in length to said base member, said flexible band being attachedalong one edge thereof to said base member by a plurality of staplesextending along the entire length of said base member, and an elongatedflat band of abrasive material substantially equal in length to saidbase member, said abrasive material being attached along one edgethereof to the opposite edge of said flexible band by adhesive extendingalong the entire length of said bands, the opposite edge of saidabrasive material being free.

2. A replaceable flexible abrasive unit for polishing large areascomprising an elongated narrow base member formed of cardboard or thelike, an elongated flat flexible band of textile material substantiallyequal in length to said base member, one edge of said flexible bandforming a loop extending around said base member, a plurality of staplesextending through and attaching both sides of said loop of textilematerial to said base member, said staples extending along the entirelength of said base member, and an elongated flat band of abrasivematerial substantially equal in length to said base member, saidabrasive band being attached along one edge thereof to References Citedin the file of this patent UNITED STATES PATENTS 2,522,920 Baltes Sept.19, 1950 2,597,421 White May 20, 1952 2,599,961 White June 10, 1952 is-m

